The invention relates to a device for infeeding a material web into a rotary printing machine, by which the material web is introducible from a reel changer through at least one printing unit and through a dryer and a chill-roller group, into various conveying paths through an angle-bar superstructure.
The published European Patent Document EP 0 038 450 B1 is concerned with an infeed device for web-fed rotary printing machines. The infeed device includes an infeed element formed of a flexible solid material which is displaceable along a tubular guide laterally of an infeeding route for the material web. The infeed element has a solid round or polygonal cross section, so that there is an almost equal bending resistance in all directions transverse to the longitudinal axis of the infeed element. The infeed element is guided in a tubular guide formed with a slit, and has a pulling hook projecting laterally out of the slit formed in the guide. The infeed element is driven by one or more driven friction-wheel pairs. Due to the solid polygonal or round cross section, the infeed device according to the aforementioned published European patent document requires a relatively large amount of space as it passes through the individual printing units.
The published European Patent Document EP 0 613 776 B1 is concerned with a profile bar for guiding a roller chain. The profile bar has an approximately C-shaped profile with a base member and two mutually parallel legs extending perpendicularly to the base member and, respectively, formed with a longitudinal groove or slot for accommodating therein and for guiding a roller chain movable in the profile bar and serving for drawing paper into a web-fed rotary printing machine. One of the legs is formed with openings extending through the leg and being spaced apart from one another in the travel direction of the roller chain. The openings are formed as slits passing through the entire length of the leg, which extends at right angles from the base member. The roller chain takes up a given minimum overall height, likewise, due to which the installation space, which is, in any case, rather tight in the printing unit, is additionally restricted.
The published German Patent Document DE 198 02 194 A1 relates to a web-infeed device for a rotary printing machine. The length of a flexible, open-ended infeed element is somewhat greater than the distance between the spaced-apart drive units. Of these, a number are provided for moving the infeed element in guides and diverters along the infeed route. Switches for switching the respectively required drive element on, and for simultaneously switching off the drive element no longer required, are provided along the infeed route, the switches being actuatable by the infeed element, which is provided with a coating for reducing the friction in the guide.
In this web-infeed device, a multiplicity of additional components, such as balls, for example, are required which are positionable in cages, rings or cutouts in the infeed element which are adapted to or matched with other geometries, thus constituting additional outlay or expense.
The published Japanese Document Hei 2-265 848 is concerned with a device for infeeding the paper for a rotary printing machine. In this construction, the web which is to be introduced is guided from a paper-reel mounting, via a printing unit, up to a folder. A guide path is formed along the web path predetermined by the machine components. An infeed element for introducing the paper web is of tape-shaped construction and is formed with regularly arranged recesses and elevations on at least one side. It is also possible for openings to pass right through the tape-shaped infeed element. Also provided on the tape-shaped infeed element is a take-up section for the start of the material web, which is to be fastened and threaded in. A drive system formed of a multiplicity of drive stations engages in the openings or recesses, or the elevations of the tape-shaped infeed element in order to guide the latter through the rotary printing machine.
In view of the aforedescribed prior state of the art, it is an object of the invention to provide a device for infeeding a material web into a rotary printing machine, wherein the operational reliability of the improved infeed device is increased, buckling resistance of the infeed device is improved, and the number of conveying elements and drive elements, respectively, such as balls, for example, are reduced.
With the foregoing and other objects in view, there is provided in accordance with one aspect of the invention, a a device for infeeding a material web along an infeed path into a rotary printing machine, including drive stations arranged along the infeed path, and an infeed element partially enclosed by a guide formed with a lateral opening at which a material web is fastenable on an extension piece, comprising a profiling provided on the infeed element for stiffening the infeed element in an advancement direction along the infeed path.
In accordance with another feature of the invention, the drive stations, respectively, include drive rollers, respectively, formed with a cylindrical jacket surface.
In accordance with a further feature of the invention, the drive stations, respectively, include drive rollers having jacket surfaces, respectively, matching with or adjusted to the profiling of the infeed element.
In accordance with an added feature of the invention, the jacket surfaces of respective pairs of the drive rollers of the drive stations are respectively convexly and concavely curved.
In accordance with an additional feature of the invention, the infeed element is convexly/concavely curved perpendicularly to the advancement direction thereof along the infeed path.
In accordance with yet another feature of the invention, the infeed element has a wave-shaped profile.
In accordance with yet a further feature of the invention, the profiled infeed element has an adjoining planar extension.
In accordance with yet an added feature of the invention, the infeed element is formed with a U-shaped profile having a given depth of curvature.
In accordance with yet an additional feature of the invention, the guide enclosing the infeed element is formed complementarily to the infeed element.
In accordance with still another feature of the invention, the infeed element merges, from a profiling upline from a deflection, into a planar-abutment position and, from the latter, rapidly resumes a profiling downline from the deflection.
In accordance with still a further feature of the invention, the drive rollers are formed of yieldable material adaptable to the profiling.
In accordance with still an added feature of the invention, the infeed element is formed of spring steel.
In accordance with still an additional feature of the invention, during passage of the infeed element through a drive station with cylindrical drive rollers, the profiling of the infeed element fades away from the infeed element in an engagement region and, after passage through the drive station, is restored to the infeed element.
In accordance with another aspect of the invention, there is provided a rotary printing machine with a device for infeeding a material web along an infeed path into the rotary printing machine, including drive stations arranged along the infeed path, and an infeed element partially enclosed by a guide formed with a lateral opening at which a material web is fastenable on an extension piece, comprising a profiling provided on the infeed element for stiffening the infeed element in an advancement direction along the infeed path.
In accordance with a concomitant aspect of the invention, there is provided a newspaper rotary printing machine with a device for infeeding a material web along an infeed path into the rotary printing machine, including drive stations arranged along the infeed path, and an infeed element partially enclosed by a guide formed with a lateral opening at which a material web is fastenable on an extension piece, comprising a profiling provided on the infeed element for stiffening the infeed element in an advancement direction along the infeed path.
The advantages of the construction according to the invention can be seen in that profiling the infeed element relative to the advancement direction thereof can increase the buckling resistance thereof to a considerable extent, with the result that it is possible to dispense with the integration of conveying and drive elements, such as balls, for example, in the infeed element. The profiling may be impressed on the material of the infeed element over rectilinearly extending passages of the infeed path; during passage through 90xc2x0 deflections or 180xc2x0 deflections, the profile is forced out of the infeed element, and is then reestablished therein after the infeed element has passed the deflecting element. The individual drive stations by which the infeed element is conveyed through the rotary printing machine may be arranged farther apart from one another because, due to the profiling, there is a drastic reduction in the friction of the infeed element in the guide enclosing it.
In an advantageous configuration of the concept upon which the invention is based, the infeed element is driven via a drive station which includes drive rollers having a cylindrical jacket surface. The jacket surfaces grip the profiled infeed element and smooth the latter in the engagement region until, following the passage of the infeed element through the drive nip between the two drive rollers, the infeed element resumes the originally profiled shape thereof. Instead of drive stations with drive rollers having cylindrical jacket surfaces, it is also possible to provide drive rollers of which the jacket surfaces correspond to the profiling of the infeed element. The drive rollers may have, for example, a convexly/concavely curved jacket surface, the infeed element being conveyed between the drive rollers and through the nip therebetween by friction.
The profiling of the infeed element may extend in wave-shaped form, in order to increase buckling resistance; on the other hand, the profiling of the infeed element may comprise a straightforward circular segment-shaped curvature which is adjoined by a planar extension projecting from the lateral opening of the guide. The infeed element may also have an approximately U-shaped profile, with a somewhat more pronounced curvature relative to the center of curvature.
The guide which encloses the profiled infeed element for material webs is formed complementarily to the contour of the infeed element, thereby making it possible to achieve particularly low-friction guidance along the advancement path of the infeed element.
For pronounced deflections, for example a 90xc2x0 deflection or 180xc2x0 deflection, the profiling of the infeed element merges, as the infeed element abuts the jacket or lateral surface of a deflecting roller, into a planar-abutment position of the infeed element against the lateral surface, before the infeed element regains the profiling thereof after the infeed element has passed the deflection. The drive rollers or the deflecting rollers for the infeed element are preferably formed of a yieldable or pliant material which adapts to the profiling of the infeed element. The infeed element by itself is preferably formed, for example, of extremely thin spring steel material, which allows the profiling to fade away briefly from the infeed element, but subsequently resumes the profiling. This is particularly advantageous when the infeed element runs through pronounced deflections of 90xc2x0 or 180xc2x0.
The construction proposed in accordance with the invention can be particularly advantageous in jobbing presses or newspaper presses wherein a multiplicity of different web paths have to be realized in the angle-bar superstructure in order to put together a great variety of copies.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a device for infeeding a material web into a rotary printing machine, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, wherein: